DE-B 2,140,733 discloses a container of the above type and adapted to contain ready-made dishes to be warmed up in boiling water of an oven, such as a microwave oven, said container comprising a tray-shaped bottom part of aluminium and a cover part of aluminium sealed to the bottom part along the rim thereof. Weakening lines divide the cover part into three portions, each portion being provided with a gripping member to be gripped when the portion in question of the cover part is to be removed from the bottom part.
Correspondingly, DK-B 160,702 discloses a container of the above type and comprising a tray-shaped bottom part and a peelable cover sheet of polyester. This container is also suited for freezing and storing articles of food and can be used later on in connection with the warming up of said article of food in an oven, such as a microwave oven.
Further, DE-A1 2,840,223 discloses a tobacco pouch of plastic sheet with an opening closed by means of a peelable closure strip.
Moreover, U.S. Pat. No. 1,320,757 discloses a sheet metal container of the type comprising a cover soldered to a lower part along lines of solder. The cover may be torn away along said lines to open the container. The cover comprises two cover sheets of metal soldered together along an obliquely extending line which intersects the side walls of the container at angles. Furthermore, each cover sheet soldered to the rim of the container wall. At a corner of the overlapping area between the two cover sheets each cover sheet is provided with a tongue, which may be gripped for removing the cover sheet in question. According to the publication, it is possible to remove the cover by hand without using a key. However, it should be considered very doubtful whether it will be possible to break the solder connection and thereby tear off the cover sheet without using tools, such as a key. Under all circumstances, tearing off the cover sheet without using a tool requires such a strength and is connected with such a risk of cutting oneself that very few persons would make the attempt at all.
Finally, FR-B1-319,186 discloses a sheet metal container essentially only differing from the container according to U.S. Pat. No. 1,320,757 in that a gripping ring is attached to the tongue for tearing off the cover sheet in question by hand.
U.S. Pat. No. 1,320,757 and FR-B1-319,186 thus relate to a completely different type of packing than the present invention.